David Walsh Blog

• By David WalshJanuary 31, 2023

  How to Open an App from Anywhere on Mac Command Line

  Many engineers like myself live in the command line, and perform actions from command line that most others would click an icon for. I've always found opening apps from command line on Macs painful. You need to references the Applications directory, add .app to...

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• By David WalshJanuary 30, 2023

  How to Create a Diff of Two Images

  When I was a child, I loved looking for Waldo in the "Where's Waldo?" book series. These days I'm a sucker for TMZ's "What's the Big Frigin Difference" images, where TMZ slightly changes an image and you have to spot the differences between the two.

• By David WalshJanuary 17, 2023

  5 Web Design Trends for 2023 That You Should Pay Attention To

  The start of a new year is usually a time when we start looking for ways to make something a little better. That something could be our life, work, or what we produce. Web designers, for example, might look for ways to make their designs more...

• By David WalshJanuary 16, 2023

  fetch with Timeout

  A few years back I wrote a blog post about how write a fetch Promise that times out. The function was effective but the code wasn't great, mostly because AbortController , which allows you to cancel a fetch Promise, did not yet exist. With...

• By David WalshJanuary 9, 2023

  Customizing HTML Form Validation

  Form validation has always been my least favorite part of web development. You need to duplicate validation on both client and server sides, handle loads of events, and worry about form element styling. To aid form validation, the HTML spec added some new form attributes...

• By David WalshJanuary 3, 2023

  How to Determine a JavaScript Promise’s Status

  Promises have changed the landscape of JavaScript. Many old APIs have been reincarnated to use Promises (XHR to fetch, Battery API), while new APIs trend toward Promises. Developers can use async/await to handle promises, or then/catch/finally with callbacks, but what Promises don't tell...

• By David WalshJanuary 2, 2023

  Detect XR Support with JavaScript

  A few years ago I wrote an article about how to detect VR support with JavaScript. Since that time, a whole lot has changed. "Augmented reality" became a thing and terminology has moved to "XR", instead of VR or AR. As such...

• By David WalshDecember 30, 2022

  Document.elementFromPoint

  Reacting to events with JavaScript is the foundation of a dynamic experiences on the web. Whether it's a click event or another typical action, responding to that action is important. We started with assigning events to specific elements, then moved to event delegation...

• By David WalshDecember 29, 2022

  Detect Browser Bars Visibility with JavaScript

  It's one thing to know about what's in the browser document, it's another to have insight as to the user's browser itself. We've gotten past detecting which browser the user is using, and we're now into knowing what pieces of the browser UI users are...

• By David WalshDecember 29, 2022

  JavaScript print Events

  Media queries provide a great way to programmatically change behavior depending on viewing state. We can target styles to device, pixel ratio, screen size, and even print. That said, it's also nice to have JavaScript events that also allow us to change behavior. Did...